A kind of preparation method of conductive nano laminated film
Technical field
The invention belongs to technical field of polymer composite materials, be specifically related to a kind of preparation method of conductive nano laminated film.
Background technology
In recent years, the feature such as can to regulate in the larger context because conducting polymer materials has good stability and resistivity, be widely used in the industries such as electronics, communication, thermal control, the energy.But prepared the conductivity of laminated film and mechanical property not good, the conductivity and the mechanical property that therefore improve laminated film are extremely important.In raising plastics film conduction and mechanical property technology, solution blending utilizes intermolecular interaction good between nano conducting powders and polymkeric substance and nanoparticle excellent conductive performance to improve mechanical property and the conductivity of polymeric matrix, have that processing is easy, product cost is high and be beneficial to the advantages such as recovery, become the focus and emphasis of research both at home and abroad.The Nano filling seeking to have satisfactory electrical conductivity and mechanical property becomes the key improving conducting polymer and mechanical property research.
Redox graphene (RGO), its structure is plane hexagonal lattice, and each carbon atom is sp
2hydridization also provides the electronics on residue P track to form large π key, a large amount of electronics can move freely and make its conductivity excellent (specific conductivity ~ 6000S/cm) in crystal, and the speed at room temperature transmitting electronics is all rapider than known conductor, so RGO becomes the desirable Nano filling of the one improving polymer conductivity.Application number is that (applying date is on 04 22nd, 2013 to CN201310139855, publication number is CN103236324A, publication date is on 08 07th, 2013) the preparation method of a kind of flexible transparent conductive film based on redox graphene of Chinese patent, by Cement Composite Treated by Plasma polyethylene terephtalate substrate, it is made to bring hydrophilic radical, then on wetting ability PET substrate, the graphene oxide film of dispersion is prepared by bar type coating technology, be less than or equal under 100 DEG C of conditions, the graphene oxide film obtained is dipped in hydroiodic acid HI solution and reduces, obtain redox graphene conductive film, the redox graphene coat film prepared by this inventive method not only flexility is good, light transmission is high, technique is simple, and excellent conductivity, in conduction field, there is potential actual application value.
China Science & Technology University Bao Chen is exposed in June, 2012 Ph.D. Dissertation " preparation method of Graphene and typical polymers nano composite material thereof, structure and study mechanism ", by solution composite approach, PVA solution and graphene solution has been mixed with out Graphene/PVA nano composite material.Result shows when Graphene content is 1.6vol%, and the specific conductivity of laminated film is 10
-8s/m, improve 7 orders of magnitude compared to pure PVA, the rate of increase of normal temperature stretch test result display tensile modulus is 12%-71%, the rate of increase of tensile strength is 6%-66%, compared to pure PVA, tensile modulus and the tensile strength of nano composite material are all significantly increased, and this composite membrane can be used in packaging industry.
Pang etc. (2010 " MaterialsLetters " 64 volume: 2226-229) in paper " Anelectricallyconductingpolymer/graphenecompositewithave rylowpercolationthreshold " by by after graphene oxide solution and Ultra high molecular weight polyethylene particles Homogeneous phase mixing ultrasonic agitation 2h, add hydrazine hydrate reduction graphene oxide, after solvent evaporation, redox graphene lamella covers on Ultra high molecular weight polyethylene particles, pours mixing solutions into 10 × 10 × 2mm after preheating 5min
3mould at 200 DEG C, hot pressing 5min under 10MPa condition, cold pressing after cool to room temperature 5min, namely obtains the laminated film of RGO/UHMWPE isolation structure.Test result display percolation threshold
vol.%.When redox graphene content is 0.6vol%, the specific conductivity of laminated film is up to 10
-1s/m, but mechanical property raising is not clearly.
More than study is made evenly and the laminated film of isolation structure by solution combined and pressure sintering respectively, can find out that the laminated film of isolation structure obtains significant raising compared to the electroconductibility of the laminated film of uniform texture, but the isolation structure thin film mechanical performance prepared by this method is very poor.Up to the present, also under the action of a magnetic field, do not prepare about adding magnetic particle the report that isolation structure improves conductivity and mechanical property laminated film.
Summary of the invention
The object of this invention is to provide a kind of preparation method of conductive nano laminated film, solve the problem that isolation structure thin film mechanical performance that prior art obtains is very poor.
The technical solution adopted in the present invention is, a kind of preparation method of conductive nano laminated film, and concrete steps are as follows:
Step 1, passes into N by after graphene oxide (GO) and polyvinylpyrrolidone (PVP) in deionized water ultrasonic agitation 1h
2; Then FeCl is added
24H
2o and FeCl
36H
2o; Dropwise adding ammoniacal liquor afterwards makes the pH value of solution be 11, after high-speed stirring reaction, temperature is elevated to 70 DEG C of slaking 1h; Then stop passing into N
2, dropwise add hydrazine hydrate, high-speed stirring 2h under 98 DEG C of conditions, after spending Ion Cleaning, and be mixed with the RGO-Fe that concentration is 0.25mg/ml
3o
4solution;
Step 2, by polyvinyl alcohol solution and RGO-Fe
3o
4solution mixes, and ultrasonic agitation, to evenly, obtains PVA/RGO-Fe
3o
4mixing solutions; By PVA/RGO-Fe
3o
4mixing solutions is poured in polystyrene (PS) ware, is positioned on rectangle magnet and leaves standstill 12h, then drying at room temperature, obtain conductive nano laminated film at 30 ~ 35 DEG C.
Feature of the present invention is also,
In step 1, the preparation method of graphene oxide is: expansible black lead is joined the dense H that concentration is 98%
2sO
4in, stir in ice-water bath, then add KMnO gradually
4reaction, control temperature of reaction at 10 ~ 15 DEG C, 2h is carried out in reaction, continues reaction 1h subsequently in 35 DEG C of waters bath with thermostatic control; Successively add the H of deionized water and concentration 30%
2o
2, filtered while hot after stirring, obtains pasty mixture, is first the HCl solution washing of 5% by concentration, then uses deionized water repetitive scrubbing until without SO in filtrate
4 2-, then utilize ultrasonication to be scattered in deionized water, finally at 50 DEG C, dry 48h obtains graphene oxide.
The dense H of every 100ml
2sO
4in add 2 ~ 4g expansible black lead.
KMnO
4quality be 3 ~ 5 times of expansible black lead quality.
Dense H
2sO
4, deionized water and H
2o
2volume ratio be 100:400 ~ 800:5 ~ 10.
The volume of HCl solution is 1 ~ 2 times of mashed prod volume.
In step 1, the mass ratio of graphene oxide and polyvinylpyrrolidone is 1:1 ~ 2.
FeCl in step 1
24H
2the mass ratio of O and graphene oxide is 1:0.5 ~ 1.5; FeCl
36H
2the mass ratio of O and graphene oxide is 1:0.2 ~ 0.6; The mass ratio of hydrazine hydrate and graphene oxide is 10:1.
Polyvinyl alcohol (PVA) solution and RGO-Fe in step 2
3o
4the volume ratio of solution is 1:1 ~ 1.5.
The invention has the beneficial effects as follows, the preparation method of conductive nano laminated film of the present invention, the PVA/RGO-Fe of preparation
3o
4the nano composite membrane not only feature of environmental protection is good, and obtains significant raising containing the nano compound film of graphene oxide relative to the conductivity of pure PVA film and mechanical property.In addition, preparation method's technique of matrix material provided by the invention is simple, and security is high, with low cost, has very large practical and popularizing value.
Accompanying drawing explanation
Fig. 1 is the TEM figure of conductive nano laminated film prepared by the present invention;
Fig. 2 is conductive nano laminated film isolation structure film forming figure prepared by the present invention;
Fig. 3 is conductive nano laminated film electrical conduction mechanism figure prepared by the present invention.
Embodiment
Below in conjunction with the drawings and specific embodiments, the present invention is described in detail.
The preparation method of conductive nano laminated film of the present invention, specifically implements according to following steps:
Step 1, joins the dense H that concentration is 98% by expansible black lead
2sO
4in, the dense H of every 100ml
2sO
4in add 2 ~ 4g expansible black lead, stir in ice-water bath, then add KMnO gradually
4reaction, KMnO
4quality be 3 ~ 5 times of expansible black lead quality, control temperature of reaction at 10 ~ 15 DEG C, 2h is carried out in reaction, continues reaction 1h subsequently in 35 DEG C of waters bath with thermostatic control; Successively add the H of deionized water and concentration 30%
2o
2, dense H
2sO
4, deionized water and H
2o
2volume ratio be 100:400 ~ 800:5 ~ 10, filtered while hot after stirring, obtains pasty mixture, is first the HCl solution washing of 5% by concentration, the volume of HCl solution is 1 ~ 2 times of mashed prod volume, then uses deionized water repetitive scrubbing until without SO in filtrate
4 2-, then utilize ultrasonication to be scattered in deionized water, finally at 50 DEG C, dry 48h obtains graphene oxide;
Step 2, passes into N by after graphene oxide (GO) and polyvinylpyrrolidone (PVP) in deionized water ultrasonic agitation 1h
2; The mass ratio of graphene oxide and polyvinylpyrrolidone is 1:1 ~ 2, then adds FeCl
24H
2o, FeCl
36H
2o (FeCl
24H
2the mass ratio of O and graphene oxide is 1:0.5 ~ 1.5; FeCl
36H
2the mass ratio of O and graphene oxide is 1:0.2 ~ 0.6) aqueous solution; Dropwise adding ammoniacal liquor afterwards makes the pH value of solution be 11, after high-speed stirring reaction, temperature is elevated to 70 DEG C of slaking 1h; Then stop passing into N
2, dropwise add hydrazine hydrate (mass ratio of hydrazine hydrate and graphene oxide is 10:1), high-speed stirring 2h under 98 DEG C of conditions, after spending Ion Cleaning, and is mixed with the RGO-Fe that concentration is 0.25mg/ml
3o
4solution;
Step 3, by polyvinyl alcohol (PVA) solution and RGO-Fe
3o
4solution is that 1:1 ~ 1.5 mix by volume, and ultrasonic agitation, to evenly, obtains PVA/RGO-Fe
3o
4mixing solutions; By PVA/RGO-Fe
3o
4mixing solutions is poured in polystyrene (PS) ware, is positioned on rectangle magnet and leaves standstill 12h, then drying at room temperature, obtain conductive nano laminated film at 30 ~ 35 DEG C.
The TEM figure of conductive nano laminated film prepared by Fig. 1 the present invention, can find out Fe by Fig. 1
3o
4the surface of what nanoparticle was even, orderly be coated on RGO, thus provide the magnetic of RGO, can ensure that RGO carries out moving and aligning along magnetic line of force direction under the influence of a magnetic field;
The mechanism of action of the present invention is: isolated form polymer composites can produce the current carrier (electronics, hole or ion etc.) of sufficient amount, wants to form conductive channel in macromolecular chain with interchain.The general mechanism of Here it is Thin film conductive.Adopt RGO-Fe prepared by method provided by the invention
3o
4, under ultrasonic dissociation, can be dispersed in deionized water, and define the laminated film of isolation structure under the effect of induced by magnetic field and PVA solution.As shown in Figure 2, owing to adding magnetic particle, therefore, RGO-Fe
3o
4under induced by magnetic field effect, form orientation, define relatively orderly conductive channel, laminated film presents isolation structure, ensures the formation of conductive channel, only adds the RGO-Fe of 5wt%
3o
4,its specific conductivity can reach 8.6 × 10
-2s/m.Owing to there is strong hydrogen bond action in this isolation structure, therefore, the mechanical property of polymkeric substance is also improved between PVA-RGO.Work as RGO-Fe
3o
4when content is 5wt%, its tensile strength has brought up to 80MPa by 60MPa.
Significantly can also find out from Fig. 2 under the acting in conjunction of magnetic particle and PVA, define the laminated film of isolation, thus define interconnective conductive network, be conducive to the conductivity improving laminated film.
Fig. 3 is conductive nano laminated film electrical conduction mechanism figure prepared by the present invention, Fe as seen from Figure 3
3o
4nanoparticle is coated on RGO surface, graphite flake layer is overlapped mutually and forms more conductive network, advantageously in the conductivity improving laminated film.
Embodiment 1
Step 1, joins the dense H of 250ml by 5g expansible black lead
2sO
4in, stir in ice-water bath; Then 20gKMnO is added gradually
4, carry out 2h 10 DEG C of reactions; In mixture, the H of 500ml deionized water and 10ml concentration 30% is successively added after continuing reaction 1h subsequently in 35 DEG C of waters bath with thermostatic control
2o
2, stir mixture filtered while hot, with HCl solution washing and a large amount of deionized water repetitive scrubbing until without SO in filtrate
4 2-, then utilize ultrasonication to be scattered in deionized water, finally at 50 DEG C, dry 48h obtains graphene oxide;
Step 2, adds the dispersion of 200ml deionized water for ultrasonic by 0.05g graphene oxide, 0.06gPVP, obtains graphene oxide solution and pass into N in solution
2, then add 0.1gFeCl
24H
2o and 0.25gFeCl
36H
2o, then adds ammoniacal liquor and regulates pH to be that at 11,25 DEG C after high-speed stirring 5min, be warmed up to 70 DEG C of slaking 1h, then stopping passes into N
2, instillation 0.5g hydrazine hydrate, high-speed stirring 2h under 90 DEG C of conditions, filters after deionization washing, is then configured to the RGO-Fe that concentration is 0.25mg/ml
3o
4solution;
Step 3, gets 12.5mlRGO-Fe
3o
4solution and 12.5ml concentration be 10% PVA solution mix, ultrasonic agitation 20min under 90 DEG C of conditions, obtains PVA/RGO-Fe
3o
4homogeneous mixture solotion; Then solution being poured into diameter is in the PS ware of 90mm, is statically placed in rectangle magnet 12h, then it is taken out from magnet, can obtain laminated film after drying at room temperature under 30 DEG C of conditions.
Embodiment 2
Step 1, joins the dense H of 250ml by 5g expansible black lead
2sO
4in, stir in ice-water bath; Then 17.5gKMnO is added gradually
4, carry out 2h 12 DEG C of reactions; In mixture, the H of 1500ml deionized water and 25ml concentration 30% is successively added after continuing reaction 1h subsequently in 35 DEG C of waters bath with thermostatic control
2o
2, stir mixture filtered while hot, with HCl solution washing and a large amount of deionized water repetitive scrubbing until without SO in filtrate
4 2-, then utilize ultrasonication to be scattered in deionized water, finally at 50 DEG C, dry 48h obtains graphene oxide;
Step 2, adds the dispersion of 200ml deionized water for ultrasonic by 0.1g graphene oxide, 0.2gPVP, obtains graphene oxide solution and pass into N in solution
2, then add 0.1gFeCl
24H
2o and 0.25gFeCl
36H
2o, adds ammoniacal liquor and regulates pH to be that at 11,25 DEG C after high-speed stirring 5min, be warmed up to 70 DEG C of slaking 1h, then stopping passes into N
2, instillation 1g hydrazine hydrate, high-speed stirring 2h under 98 DEG C of conditions, filters after deionization washing, is then configured to the RGO-Fe that concentration is 0.25mg/ml
3o
4solution;
Step 3, gets 15mlRGO-Fe
3o
4solution and 10ml concentration be 10% PVA solution mix, ultrasonic agitation 20min under 90 DEG C of conditions, obtains PVA/RGO-Fe
3o
4homogeneous mixture solotion; Then solution being poured into diameter is in the PS ware of 90mm, is statically placed in rectangle magnet 12h, then it is taken out from magnet, can obtain laminated film after drying at room temperature under 32 DEG C of conditions.
Embodiment 3
Step 1, joins the dense H of 167ml by 5g expansible black lead
2sO
4in, stir in ice-water bath; Then 15gKMnO is added gradually
4, carry out 2h 15 DEG C of reactions; In mixture, the H of 1336ml deionized water and 8.35ml concentration 30% is successively added after continuing reaction 1h subsequently in 35 DEG C of waters bath with thermostatic control
2o
2, stir mixture filtered while hot, with HCl solution washing and a large amount of deionized water repetitive scrubbing until without SO in filtrate
4 2-, then utilize ultrasonication to be scattered in deionized water, finally at 50 DEG C, dry 48h obtains graphene oxide;
Step 2, adds the dispersion of 200ml deionized water for ultrasonic by 0.15g graphene oxide, 0.18gPVP, obtains graphene oxide solution and pass into N in solution
2, then add 0.1gFeCl
24H
2o and 0.25gFeCl
36H
2o, adds ammoniacal liquor and regulates pH to be that at 11,25 DEG C after high-speed stirring 5min, be warmed up to 70 DEG C of slaking 1h, then stopping passes into N
2, instillation 1.5g hydrazine hydrate, high-speed stirring 2h under 95 DEG C of conditions, filters after deionization washing, is then configured to the RGO-Fe that concentration is 0.25mg/ml
3o
4solution;
Step 3, gets 10mlRGO-Fe
3o
4solution and 12ml concentration be 10% PVA solution mix, ultrasonic agitation 20min under 90 DEG C of conditions, obtains PVA/RGO-Fe
3o
4homogeneous mixture solotion; Then solution being poured into diameter is in the PS ware of 90mm, is statically placed in rectangle magnet 12h, then it is taken out from magnet, can obtain laminated film after drying at room temperature under 35 DEG C of conditions.
By PVA/RGO-Fe prepared by embodiment 2
3o
4nano compound film, owing to achieving the reduction greatly to Graphene at a higher temperature, makes by Fe
3o
4the coated Graphene of nanoparticle defines more conductive network in PVA matrix, makes laminated film conductivity obtain significant raising relative to pure PVA; Because isolation structure exists strong hydrogen bond action between PVA-RGO, the mechanical property of polymkeric substance is made to have also been obtained raising.